Procedure and machinery for the molding and assembling of an assembled object

ABSTRACT

The invention concerns a procedure and a machinery for molding and assembling of at least two part objects ( 4 ) and ( 8 ) of plastics, e.g. two ball shells, which can be assembled to a hollow ball ( 4+8 ), as molding and assembly can take place in same tool and continuously in the same work procedure. This can be realized by the two turnable middle parts ( 6 ) and ( 6 &#39;) of the tool, respectively are supplied with the mold cavities ( 5 ) and ( 7 ), where the assembling of the part objects ( 4 ) and ( 8 ) can take place, when the respective tool cavities meet during the rotation, at the same time as the closing of the mold. During the closing there can simultaneously be molded new part objects ( 4 &#39;&#39;) and ( 8 &#39;&#39;) in the opposite placed mold cavities ( 5 &#39;&#39;) and ( 7 &#39;&#39;) in the two turnable mold part ( 6 ) and ( 6 &#39;). If it is necessary in respect of the material or the design of the part objects, there can after the molding of the part objects be applied e.g. heat on the respective boundary surfaces, which shall shape the assembling. This can suitably be fit into the steps, which the turnable middle parts ( 6 ) and ( 6 &#39;) run through. The part objects ( 4 ) and ( 8 ) can possibly as well as be assembly by a snap- or click function, which is a pure mechanical assembling.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention concerns a procedure and machinery for molding andassembling of an in at least two part objects molded object preferablyof plastics in a tool comprising at least one turnable and/ordisplaceable middle part.

2. Description of the Related Art

There is known other procedures and machineries for the molding andassembling of plastic parts in tools with a turnable middle part. Thusthere in my international patent application PCT No. DK/98/00034 aredescribed turnable middle parts, which enables the use of the so calledstack molding technique in multi component molding, where you moldassembled plastic parts.

For plastic objects, which normally cannot be molded with a cavitybecause of the shape of the core or of complicated geometries, you haveat injection molding normally molded the object in two halves andassembled them afterwards outside the molding machine.

The hitherto known procedures and machineries for assembling or moldingof such objects normally involve, that you apply assembling- and weldingmachines to achieve these objects with cavities, where it is notpossible to achieve the desired geometries in another way than by usinge.g. various blow molding techniques.

BRIEF SUMMARY OF THE INVENTION

The procedure and the machinery according to the invention is intendedto combine the above mentioned technology with the likewise knownassembling technique, but here in one and the same tool, whereby therecan be achieved large improvements of productivity.

The procedure according to the invention is characterized by the fact,that there in at least one of the boundary surfaces between the parts ofthe tool, which are furnished with turnable/displaceable tool cavitiesand/or cores, occurs an assembling of the parts e.g. by welding oranother kind of assembling of at least two parts of the in the toolmolded object(s).

A more precise account for the benefits by the procedure and machineryaccording to the invention will appear from the description and thedrawing, where

BRIEF DESCRIPTION OF THE DRAWING FIGURES

FIG. 1 shows a cross section of the tool according to the invention seenfrom above,

FIG. 2 shows the same, where the turnable middle part is turned 90degrees in the direction of the arrow,

FIG. 3 shows the same, where the middle part is turned additional 90degrees, and

FIG. 4 shows the same, where the middle part is turned anotheradditional 90 degrees.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

On FIG. 1 is, seen from above, shown a section of a tool for theexercise of the procedure according to the invention. From the left isseen the stationary tool part 1 with a hot-runner furnished inlet 2,which directs the material further through the core 3. The tool is onthe figure just opened after the first part object 4 is molded in thecavity 5 in the left of the two turnable middle parts 6 through theinlet 2 and the core 3. At the same time there is in the cavity 7 in theright of the two turnable middle parts 6′ molded another part object 8with material from that with the inlet 2′ and the core 3′ furnishedmovable mold part 9. The two part objects 4 and 8 consist on the drawingof two uniform half ball shaped shells, that later is intended to be puttogether to a hollow ball. It will be noticed, that this assembling willbe eased by the outermost boundary surfaces 10 and 11 on the respectivepart objects 4 and 8 exceed out from the turnable middle parts. This isaccomplished by there are similar undercuts 12 and 12′ in respectivelythe stationary mold part 1 and the movable mold part 9. As it appearsfrom the figure both the turnable middle parts 6 and 6′, which inprinciple has a square formed section, have got their corners removed,so that they require a lesser opening of the tool for being able to turnaround. Finally shall be mentioned, that identical cross sections of theon the figure showed can be seen e.g. five places underneath the shown,if the tool is designed for producing in total six assembled objects pr.cycle.

In FIG. 2 is shown the same section, but where the two turnable middleparts 6 and 6′ both are turned 90 degrees in the direction of therespective arrows, whereby the two part objects 4 and 8 have reached theon the figure highest position. Here heat is applied on theirrespectively boundary surfaces 10 and 11 from the movable heat units 13.The tool is meanwhile preferably closed, and the two subsequent partobjects 4′ and 8′ are just being molded through the two inlets 2 and 2′and the cores 3 and 3′ in respectively the stationary mold part 1 andthe movable mold part 9.

FIG. 3 shows the same section, where the two turnable middle parts 6 and6′ both are turned additional 90 degrees in the direction of therespective arrows. The tool is here open, but moving towards closing,where the two part objects 4 and 8 will approach their two respectiveheated boundary surfaces 10 and 11 to each other before the weldingtogether. The two following part objects 4′ and 8′ are now in their onthe figure highest position, where they are receiving heat on theirrespective boundary surfaces 10′ and 11′ from the movable heat units 13.Finally the third set of part objects 4″ and 8″ are just being molded inthe mold cavities 5″ and 7″, both the part objects are finished andready for being turned away from their respective cores 3 and 3′.

On FIG. 4 the two turnable middle parts 6 and 6′ are turned anotheradditional 90 degrees. Here the tool is closed, and the two part objects4 and 8 now are melted together to the finished object, the hollow ball4+8, which on the figure just is being ejected from the tool. It isnoticed, that possible surplus material 14 suitably only exists on theinner side of the ball shell. The two following part objects 4′ and 8′are here seen during the welding of their boundary surfaces 10′ and 11′in the closed mold, and the third set of part objects 4″ and 8″ isgetting their respective boundary surfaces 10″ and 11″ heated by themovable heating units 13. Finally has the fourth set of part objects 4′″and 8′″ just been molded at their respective cores 3 and 3′.

Hereby the first sequence of the two turnable middle parts 6 and 6′ isterminated. By the next turning of 90 degrees a new molding- andassembling cycle is started, as the first, where all four sides of eachof the two turnable middle parts 6 and 6′ are in full function.Hereafter a continuous production of part objects and the assemblinghereof can continue after the same principles.

The on the drawing shown is just a single example of how the procedureand the machinery of the invention can be realized. This should howeverbe sufficient to show the fundamental principles of the invention.

However there could also have been shown other versions of the procedureand the machinery according to the invention. Thus could the two objectparts after their assembling a bottle or another kind of container. Thiscan be realized by the turnable middle parts in stead of the on thedrawing shown cavities have outgoing cores/core parts, which could makethe design of the opening of the bottle. It will likewise be seen, thatmore technical objects with a difficult geometry preferably could beproduced after the procedure according to the invention, which in allrespects provides entire new possibilities for the designing of moldedobjects.

It shall also be noticed that the on the drawing shown step by applyingheat possibly can be avoided, if e.g. the material, the design of theobject or the velocity of the movement allows this. This is e.g. alsothe case, if the part objects solely have to be assembled by a puremechanical assembling, such as a snap- or click function. E.g. in steadof the step in the movement, where heat is applied, the part objects canbe supplied with other things, such as electronics, fluid or metalparts, which shall be included in the assembled object.

1. A process for the molding and assembling of a two-part plasticobject, the process comprising the steps of: providing a machineincluding first and second rotatable molds, each mold having at leasttwo mold cavities formed therein, and each of said molds having androtatable on a substantially vertically orientated axis of rotation;introducing plastic into one of said mold cavities in said firstrotatable mold, to form a part, at a first forming position located at adistal facing side of said first rotatable mold; introducing plasticinto one of said mold cavities in said second rotatable mold, to form apart, at a second forming position located at a distal facing side ofsaid second rotatable mold; rotating said rotatable molds; and joiningparts in opposing mold cavities at an assembly position when one of saidmold cavities of said first mold and one of said mold cavities of saidsecond mold are aligned intermediate to said axes of rotation; whereinthe at least two mold cavities in each mold enables said parts to besimultaneously formed at said forming positions and assembled togetherat said assembly position.
 2. The process of claim 1 wherein the stepsof introducing plastic at the forming position and joining opposingparts at the assembly position are performed simultaneously, andrepeatedly between rotating steps, to continuously produce multipleobjects.
 3. The process of claim 1 further including the step ofapplying heat to an edge of the part before the joining step.
 4. Theprocess of claim 1 further including the step of ejecting a finishedobject from said mold cavities after the joining step.
 5. The process ofclaim 1 further including the step of moving at least one of said moldsin a transverse direction perpendicular to said axis of rotation, duringthe joining step, to close together the molds at said assembly position.6. A process for the molding and assembling of a two-part plasticobject, the process comprising the steps of: providing a machineincluding first and second rotatable molds, each mold having at leasttwo mold cavities formed therein, and each of said molds having androtatable on an axis of rotation; introducing plastic into one of saidmold cavities in said first rotatable mold, to form a part, at a firstforming position located at a distal facing side of said first rotatablemold aligned with said axes of rotation; introducing plastic into one ofsaid mold cavities in said second rotatable mold, to form a part, at asecond forming position located at a distal facing side of said secondrotatable mold aligned with said axes of rotation; rotating saidrotatable molds; and joining parts in opposing mold cavities at anassembly position when one of said mold cavities of said first mold andone of said mold cavities of said second mold are aligned intermediateto said axes of rotation; wherein the at least two mold cavities in eachmold enables said parts to be simultaneously formed at said formingpositions and assembled together at said assembly position.
 7. Theprocess of claim 6 wherein the steps of introducing plastic at theforming position and joining opposing parts at the assembly position areperformed simultaneously, and repeatedly between rotating steps, tocontinuously produce multiple objects.
 8. The process of claim 6 furtherincluding the step of applying heat to an edge of the part before thejoining step.
 9. The process of claim 6 further including the step ofejecting a finished object from said mold cavities after the joiningstep.
 10. The process of claim 6 further including the step of moving atleast one of said molds in a transverse direction perpendicular to anaxis of rotation of the movable mold, during the joining step, to closetogether the molds at said assembly position.